Some 60 per cent of the prisoners in the Category A facility are serving life or indeterminate sentences for public protection, with almost half aged 50 or over and the oldest man aged 91.

Peter Clarke, HM Chief Inspector of Prisons, today said: “The vast majority were serving sentences of more than 10 years, and included some of the most challenging and complex prisoners in the country. Despite this, the prison was calm and had an atmosphere that spoke of good order, safety, security and decency.”

Inspectors found an “impressive set of initiatives and good work” which could be shared across the prison service as good practice.